C'mon... 34-Cent Stereo Amp 2x3W? 29-Cent Battery Savior?

Can these be for real? Five pcs for $1.69: http://www.ebay.com/itm/201574969988
I have a pile of 386 amps but I gotta try these out, that price seems cheaper than free. Small board.

Another noteworthy tiny board (practically microscopic at about 1/8" x 5/8"), is this 29-cent (OK, ten pcs for $2.89) Li-Ion battery protection chip, which claims to do it all. Overcharge protection, over-discharge protection, short circuit protection, overcurrent protection. I just got these in, will test soon. http://www.ebay.com/itm/162025038275

"When you make a thing, a thing that is new, it is so complicated making it that it is bound to be ugly. But those that make it after you, they don’t have to worry about making it. And they can make it pretty, and so everybody can like it when others make it after you."

I know we're not talking about high-end stereo equipment here but how do class D amplifiers compare with the more traditional analog amplifiers as far as noise and distortion? Do purists ever go with class D or is it reserved primarily for low-fidelity applications?

I know we're not talking about high-end stereo equipment here but how do class D amplifiers compare with the more traditional analog amplifiers as far as noise and distortion? Do purists ever go with class D or is it reserved primarily for low-fidelity applications?

As with everything people either love it or hate it. However lookup the NAS D 3020, a high end class D amp

Noise and THD are generally worse for class D amplifiers than for analog ones, but the NAS D 3020 specs are pretty impressive. They are at a level where 99.99% or more of audio listeners would not be able to tell the difference between the NAS and a top of the line analog amplifier.

In science there is no authority. There is only experiment.
Life is unpredictable. Eat dessert first.

"When you make a thing, a thing that is new, it is so complicated making it that it is bound to be ugly. But those that make it after you, they don’t have to worry about making it. And they can make it pretty, and so everybody can like it when others make it after you."

Great demo, glad to hear you're pleased with them. As usual, everyone gets theirs before I do!

Now you have me recalling which songs which 1980's stereo stores blasted to demo their high power stereo's dynamic range and all I come up with is Journey... Don't stop believin'!

"When you make a thing, a thing that is new, it is so complicated making it that it is bound to be ugly. But those that make it after you, they don’t have to worry about making it. And they can make it pretty, and so everybody can like it when others make it after you."

"When you make a thing, a thing that is new, it is so complicated making it that it is bound to be ugly. But those that make it after you, they don’t have to worry about making it. And they can make it pretty, and so everybody can like it when others make it after you."

"When you make a thing, a thing that is new, it is so complicated making it that it is bound to be ugly. But those that make it after you, they don’t have to worry about making it. And they can make it pretty, and so everybody can like it when others make it after you."

Luckily I had a 4 inch hole saw so I didn't have to use a jigsaw for the speaker cutouts...

Pshaw. Get a CNC like the rest of us!

For a really nifty wood-cutting CNC in action, check out Frank Howarth videos on YouTube. His CNC is a more recent acquisition, so fiddle with the later vids. Your drooling can start here:

Thanks for sharing. NOT! Now I know I can't afford my dream shop.

I have the same Dewalt Radial Arm Saw, circa 1965. Still working as well as my circa 1965 Delta (Rockwell) band saw. Handed down from my grandfather, to my father, to me. I'm sure they will last to give to my son.

Thanks for the demo! My boards arrived >10 days ago, but I'm ashamed to say I just looked them over and set them on a shelf. 200 WS2812b LEDs arrived about the same time and they got all the attention. After seeing the class D amplifier at work, I realize I've got to give it higher priority.

Now THAT'S a beautiful speaker box, Ron. It's the wood that makes it good! Is there a divider wall between the L/R speakers?

"When you make a thing, a thing that is new, it is so complicated making it that it is bound to be ugly. But those that make it after you, they don’t have to worry about making it. And they can make it pretty, and so everybody can like it when others make it after you."

"When you make a thing, a thing that is new, it is so complicated making it that it is bound to be ugly. But those that make it after you, they don’t have to worry about making it. And they can make it pretty, and so everybody can like it when others make it after you."

Now THAT'S a beautiful speaker box, Ron. It's the wood that makes it good! Is there a divider wall between the L/R speakers?

Thanks! I love those "hobby boards" from Home Depot. Their oak boards are nicer, but this little box did not warrant oak ;-)

I put some Wipe-On polyurethane on it.

I decided not to bother with with a divider in this cabinet - since the separation is only a few inches.
You can hear the distinct left/right channels and I won't be pushing big watts thru it.
The speakers were out of an old CD boombox (I taped them in so I could mark the mounting tab holes with a punch).
Might swap out the speakers for some better ones although it sounds pretty darn good with the little Class-D amps.

Try some batting in that enclosure. In an odd counter-intuitive way, the batting actually increases the apparent space of the enclosure as "seen" by the drivers, and you get a better sound (at least in the midrange, which is what those speakers are built for).

Though fiberglass is better, you can use white polyfill from Joann's -- costs something like a buck for a sheet, and you'll only need one sheet to try it out. Worth a shot for the non-ported cabinet you've made (without a CNC...).

Try some batting in that enclosure. In an odd counter-intuitive way, the batting actually increases the apparent space of the enclosure as "seen" by the drivers, and you get a better sound (at least in the midrange, which is what those speakers are built for).

Though fiberglass is better, you can use white polyfill from Joann's -- costs something like a buck for a sheet, and you'll only need one sheet to try it out. Worth a shot for the non-ported cabinet you've made (without a CNC...).

I was wondering where you could find batting - thought about ripping open an old pillow.